The female microbiome in HIV prevention, pathogenesis, and treatment.

Purpose of review: To summarize the relationship of vaginal and gut microbiomes with HIV transmission, pathogenesis, and treatment, focusing on women's health.

Recent findings: Bacterial vaginosis (i.e., vaginal microbiome dysbiosis) is a well established risk factor for HIV acquisition, and recent research focused on molecular mechanisms and biomarkers for HIV acquisition related to vaginal microbiota. Recent clinical trials reported on probiotics to treat bacterial vaginosis with the goal of HIV prevention; however, durability of treatment response remains sub-optimal. The vaginal microbiome may impact efficacy of preexposure prophylaxis (PrEP) and antiretroviral therapy (ART) in vaginal tissue, with recent literature examining vaginal microbiota and long-acting PrEP vaginal rings. Some research also suggests effects of PrEP or ART initiation on the vaginal microbiome. Regarding the gut microbiome, associations with HIV status may differ more by sexual practices than biological sex, and sex-specific roles of gut microbiota in HIV pathogenesis and treatment are unknown. Interactions of the gut microbiome with estrogens could underlie a role of gut microbiota in health of women with HIV.

Summary: The vaginal microbiome remains an important factor in HIV acquisition, prevention, and treatment in women. The gut microbiome has roles in HIV pathogenesis and treatment, but women-specific effects are unclear.